1. Technical Field
The present invention relates to an image forming apparatus and an image forming method of forming an image while switching a plurality of development portions and also reading or writing information to or from memories disposed in the development portions.
2. Related Art
In an image forming apparatus in which a development port holder is mounted with a plurality of development portions and which forms an image by switching the development portions, each of the development portions can include a memory for storing lifetime information thereof. For example, in the image forming apparatus disclosed in WO03/098356 (for example, FIG. 9A), a plurality of development portions are mounted in a rotary unit and rotated so that one of the development portions which is positioned at a position opposite a photosensitive member develops an electrostatic latent image. Each of the development portions is provided with a memory cell for storing information thereof and with a wireless communication antenna. When one of the development portions is positioned at the position opposite the photosensitive member, the antenna is disposed so as to communicate with another antenna mounted in another development portion. In addition, while one of the development portions develops the electrostatic latent image, the antenna thereof communicates with the antennas of the other development portions which do not develop the electrostatic latent image in order to read and write the information.
The inventors have found that, in an apparatus which forms an image by moving and switching development portions, it is desirable to have as long a period of time as possible until the development portion starts to perform a developing process after the development portions are switched in order to improve an image quality. It is considered that the reason for requiring a long period of time is because some time is necessary to obtain stable characteristic.
Accordingly, when the development portions are switched, it is necessary to immediately switch the development portion which finishes the developing process to the next development portion. However, when the development portions are switched quickly in this way, a known image forming apparatus may not appropriately read or write information to or from the development portions. That is because the development portions only stop for a short period of time, and some processing time is necessary for reading or writing information to and from the development portion.